I think the fun way way outshadows the negative, but I do find my worries about my kids getting bigger and deeper as they move on to new stages
1) The stakes are higher. I struggle, I really do, with trying to find the right mix of encouragement vs. pushing. To instill the value of hard work and education and yet not drive them to hate school and homework at so early of an age. To make sure they explore there interests yet not push them to spend hours in activities they don't really enjoy. I know these things will affect them throughout their lives, and I don't want to mess it up.
2) They remember everything. Seriously. You know when they are toddlers, and you have a bad day and maybe yell too much & the next day its all good again like it never happened? Its not like B holds a grudge, but he will remember and bring it up. Two weeks later. Two months later. Or when you promise you'll do something "someday" and hope they will conveniently forget it? They don't. Its all etched in there. Every good & bad experience. Sure he may not remember when he's 40, but he certainly will when he's 8.
3) They are out in the world. School is WAY different then daycare. You don't just walk in and hear about the day from the teacher. I usually pick B up from a whole different place (after care) and have NO IDEA what happened at school until he tells me...and while he seems to remember everything, relaying that information reliably is still quite tricky. He is with lots of different teachers and kids, some of who I've never met or seen. He had the same daycare teacher for years...and now he has a main teacher, substitutes, art teacher, gym teacher, spanish teacher, 6 different people that alternate picking him up and playing with him at aftercare, 2 karate instructors, etc...
4) And the world is judging them. We were in the same daycare since B was an infant. He's grown up there. The teachers see him as one of their own, and can compare him from year to year to see how he progressed. In school? He's one of many that just show up in September. They notice how he is different and have no frame of reference to how much improvement he has made or whether he may simply be having an off day. And little kids? They are ALL weird. They don't really think anything of their playmates idiosyncrasies. 6 year olds do, though. They notice & the judge & the tease & they exclude. We've only noted this on a very small scale so far, and it comes and goes (First day: A teased me and said we are not friends she doesn't like me. Next day: A and I played tag together and she is inviting me to her party and we are friends)
So yeah, its not all sunshine, but we're navigated the challenges as they come.